Apparatus for forming filaments.



I P. WILSON.

APPARATUS FOR FORMING FILAMENTS.

APPLICATION FILED JULY 20, I915.

Patented Mar. 14, 1916.

3 SHEETSASHEET I. 1

APPLICATION FILED JULY 20, I915- Patented Mar. 14, 1916.

3 SHEETSSHEET 2.

in 0 6 Eton 3 SHEETSSHEET 3- L. P. WILSON.

Patented Mar. 14-, 1916.

APPARATUS FOR FORMING FILAMENTS.

APPLICATION FILED JULY 20. 1915.

ENE canto.

LEONARD PHILIP WILSON, OF COVENTRY, ENGLAND, ASSIGNOR TO OOURTAULDSLIMITED, OF LONDON, ENGLAND.

APPARATUS FOR FORMING FILAMENTS.

Specification of Letters Patent.

Patented Mar. 14, 1916.

Application filed July 20, 1915. Serial No. 40,954.

"the aid of suitable coagulating liquids.

The continuous manufacture and production of tubular threads from suchsolutions has presented considerable difiiculties. In order that thethreads may possess attractive characteristics, such as luster andtransparency the walls of the threads must be very thin and the orificethrough which the solution issues must be of correspondingly smalldimensions. Since a tubular thread at the moment of its formation has tobe coagulated both inside and outside, constructional difficulties, (forexample as regards the means for introducing the coagulating liquid tothe interior of the thread), have hitherto prevented the attainment ofany practical process, for the manufacture of such threads.

According to this invention I provide a process and means for thecontinuous production of tubular threads having the desirablecharacteristics hereinbefore referred to. I have found that such tubularthreads can be produced with the same ease and continuity as canordinary threads of artificial silk, if the cellulose solution beprojected through an annular, or other suitable, orifice of a shapecorresponding to the crosssectional shape of the thread to be producedand in a jet which is immersed in a coagulating bath, the jet having acentral opening behind, and within, the orifice so that the coagulatingliquid in the bath itself has access, freely and automatically, to boththe interior and exterior surfaces of the incipient thread as it isbeing made and issues from the said orifice. Since one and the same bathfurnishes the coagulating liquid to both the interior and exterior ofthe thread, I thus avoid irregularities due to differences in pressure,or composition,

such as might be caused by obstructions in inaccessible and delicateparts of the apparatus if separate conduits were used to lead the liquidto the interior of the thread.

The orifice may be circular, or it may be elliptical, or of othercontinuous form provided the free access of the coagulating liquid tothe interior of the issuing thread be not interfered with.

The threads produced, on passing out of the coagulating bath, may bewound,

washed, dried, and otherwise treated, in any known, or suitable, mannerand then usually present the appearance of delicate flattened tubes, orstrlps.

This invention further consists in the continuous production of compoundthreads which are composed of tubular threads such as those hereinbeforereferred to, but having textile fibers inclosed therein. A ore-formedthread of artificial silk, or of any other suitable textile fiber,natural, or artificial, is passed from behind through the centralopening of a jet of the kind hereinbefore referred to, which is immersedin a coagulating bath, while, simultaneously, a cellulose solution isprojected through the annular, or other shaped, orifice, as hereinbeforedescribed. The coagulating liquid is thus permitted to pass in freelywith the pre-formed thread so as to. coagulate the interior of thetubular thread. This is illustrated in Figure 5, where part of the bathis shown at X, and the aforesaid jet at 1. The pre-formed thread 9, isled, from the bobbin 10, into the bath, under a glass rod 11, and thenthrough the central opening of the jet 1, and into the interior of thetubular thread 12, being formed. The compound thread may be wound,washed, dried, and otherwise treated, in any known, or suitable, manner.The outer thread thus produced is not a mere coating, or varnishing,upon the inner thread, but is an independent tube surrounding theinclosed fibers.

Instead of a pre-formed thread, a thread produced from cellulosesolution by means of a separate jet, situated in the same coagulatingbath at a suitable distance behind the annular jet, may be employed, thespinning, or formation, of the inner thread, and of the tubular thread,proceeding simultaneously. This is illustrated in Fig. 6

of the liquid, and I also avoid interruptions v where the jet 13, formaking the internal thread 14, simultaneously with the tubular thread12, is situated in the same bath (part of which is shown at X) as thatin which the tubular thread jet 1, is situated, the thread formed by thejet 13, being led through. the central opening of the jet 1, and intothe tubular thread 12, being formed.

According to this invention I also provide a jet especially suitable forspinning tubular, or compound, threads of the kind hereinbeforedescribed, the essential features of which jet are a central passagepermitting free access of the liquid of the bath to the interior of thetubular thread as it is formed; a chamber to which the cellulosesolution is fed under suitable pressure, and a continuous slit, ororifice, of annular, elliptical, or other shape corresponding to thecross-sectional shape of the required tubular thread, the solutionissuing from which slit, or orifice, is exposed freely, both inside, andoutside, to the liquid in the bath. The said jet may, for example, beconstructed as illustrated in the accompanying drawing.

Fig. 1 is a vertical section-Fig. 2 an elevation with the capremoved-Fig. 3 is an inside view of the cover and Fig. 4 is a section ofa modification, wherein the extremity of the projection 3 iscylindrical.

The jet consists of a body part 1', and a screw cap 2, the body part 1,having a conical projection 3, with a conical, or funnelshaped, centralopening 4, and an annular chamber 5, into which the supply tube. 6,opens at 7. The cap 2, has a central opening 8, of a diameter slightlygreater than the external diameter of the extremity of the conicalprojection 3, so that, when the cap 2, is in position, there is a fineannular orifice, or slit, around the extremity of the projection 3,communicating with the annular chamber 5, to which the cellulosesolution is led under pressure through the supply tube 6. Suitabledimensions may, for example, be a diameter of 2 mm. for the smallestpart of the centralopening 8, in the cap, and an external diameter of1.5 mm. for the extremity of the conical projection at its smallestpart, but other suitable dimensions can be employed. The width of theannular orifice, or slit, may be varied by adjusting the screw cap 2.This adjustability, however, is not essential, as the orifice, or slit,may, if preferred, be set permanently at a suitable width.

When the jet is in use the central opening 4, is freely open to theliquid in the coagulating bath and permits of suitable textile fibersbeing led, if desired, into the interior of the tubular thread formed atthe orifice as hereinbefore described. The jet should, of course, beconstructed of some material which is not appreciably attacked by eitherthe cellulose solution, or the coagulating liquid. I have foundplatinum 1. Apparatus for forming filaments of, the type described,comprising a jet nozzle adapted to be immersed in a setting bath andpierced by an aperture open at both ends to the setting fluid in thebath, an annular jet opening surrounding saidv aperture and means forleading to said jet openinga cellulose solution to form, on dischargetherethrough, a tubularfilament to both innerand outer surfaces of whichthe fluid of the setting bath has access, substantially as described.

2. Apparatus for forming filaments of the type described, comprising ajet nozzle adapted to be immersed in a setting bath and pierced by anaperture open at both ends to the setting fluid in the bath, an annularjet opening surrounding said aperture and means for leading to said jetopening a cellulose solution to form, on discharge therethrough, atubular filamentto both inner and outer surfaces of which the fluid ofthe setting bath has access, together with means for feeding throughsaid aperture in the nozzle a core filament inclosed by the tubularfilament as the latter is formed, substantially as described.

3. Apparatus for forming filaments of the type described, comprising ajet nozzle adapted to be immersed in a setting bath and pierced by anaperture open at both ends to the setting fluid in thebath, an annularjet opening surrounding said aperture and means for leading to said etopemng a cellulose solution to form, on discharge therethrough, atubularfilament to both inner and outer surfaces of which the fluid of thesetting bath has access, together with means for spinning a corefilament in said bath and leading said core filament through the saidaperture in the nozzle to form a core for the tubular filament as thelatter is formed.

4. Apparatus for forming filaments of the type described, comprising ajet nozzle adapted to be immersed in a setting bath and pierced by anaperture open at both ends to the setting fluid in the bath, an annularjet opening surrounding said aperture and means for leading to said jetopening a cellulose solution to form, on discharge therethrough, atubular filament to both inner and outer surfaces of which the fluid ofthe setting bath has access, together with means for spinning a multiplecore filament in said bath and leading said core filament through thesaid aperture in the nozzle to form a core for the tubular filament asthe latter is formed.

5. Apparatus for forming filaments of the type described, comprising ajet nozzle adapted to be immersed in a setting bath and pierced by anaperture open at both ends to the fluid of the bath, a cap secured toone face of said nozzle and perforated in register with the aperture inthe latter, a chamber inclosed by said cap and an annular dischargeopening from said chamber through the cap and surrounding the aperturewhich pierces the jet nozzle, for the purpose described.

6. Apparatus for forming filaments of the type described, comprising ajet nozzle adapted to be immersed in a setting bath and pierced by anaperture open at both ends to the fluid of the bath, a boss on one sideof said nozzle and pierced by said aperture, a cap secured to saidnozzle and inclosing therewith a chamber, said cap having a perforationpassing over said boss and spaced therefrom to form an annular dischargeopening from said chamber to the setting bath, for the purposespecified.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

LEONARD PHILIP WILSON.

Witnesses:

G. F. TYSON, VINCENT GIARDELIJ.

